Problemas Ao Mudar Resolução No Win 98

[acazetto]

No win 98 quando executo um script pra mudar a resolução a tela fica pela metade, já quando é executado o mesmo cod no XP o problema não ocorre.

O Script é o seguinte.

Código em um módulo .bas

Public Type RECT
    Left As Long
    Top As Long
    Right As Long
    Bottom As Long
End Type

Public Declare Function GetClipCursor Lib "user32.dll" (lprc As RECT) As Long

Private Declare Function EnumDisplaySettings Lib "user32" Alias _
"EnumDisplaySettingsA" (ByVal lpszDeviceName As Long, ByVal iModeNum As Long, _
lpDevMode As Any) As Boolean

Private Declare Function ChangeDisplaySettings Lib "user32" Alias _
"ChangeDisplaySettingsA" (lpDevMode As Any, ByVal dwflags As Long) As Long

Const CCDEVICENAME = 32
Const CCFORMNAME = 32
Const DM_PELSWIDTH = &H80000
Const DM_PELSHEIGHT = &H100000

Private Type DEVMODE
    dmDeviceName As String * CCDEVICENAME
    dmSpecVersion As Integer
    dmDriverVersion As Integer
    dmSize As Integer
    dmDriverExtra As Integer
    dmFields As Long
    dmOrientation As Integer
    dmPaperSize As Integer
    dmPaperLength As Integer
    dmPaperWidth As Integer
    dmScale As Integer
    dmCopies As Integer
    dmDefaultSource As Integer
    dmPrintQuality As Integer
    dmColor As Integer
    dmDuplex As Integer
    dmYResolution As Integer
    dmTTOption As Integer
    dmCollate As Integer
    dmFormName As String * CCFORMNAME
    dmUnusedPadding As Integer
    dmBitsPerPel As Integer
    dmPelsWidth As Long
    dmPelsHeight As Long
    dmDisplayFlags As Long
    dmDisplayFrequency As Long
End Type

Dim DevM As DEVMODE

Public Sub ChangeRes(iWidth As Single, iHeight As Single)
    Dim a As Boolean
    Dim i As Long
    Do
        a = EnumDisplaySettings(0&, i, DevM)
        i = i + 1
    Loop Until (a = False)

    Dim b As Long
    DevM.dmFields = DM_PELSWIDTH Or DM_PELSHEIGHT
    DevM.dmPelsWidth = iWidth
    DevM.dmPelsHeight = iHeight
    b = ChangeDisplaySettings(DevM, 0)
End Sub

Agora no Form digite o seguinte:

Dim ResX As Single
Dim ResY As Single
Dim OldResX As Single
Dim OldResY As Single
Dim Resolucao As Boolean

Private Sub Form_Load()
    
    ResX = 640
    ResY = 480
    
    Dim r As RECT
    Call GetClipCursor(r)
    OldResX = r.Right
    OldResY = r.Bottom
    If OldResX <> ResX And OldResY <> ResY Then
        Resolucao = True
        Call ChangeRes(ResX, ResY)
    Else
        Resolucao = False
    End If
End Sub

Private Sub Form_Unload(Cancel As Integer)
    If Resolucao = True Then
        Call ChangeRes(OldResX, OldResY)
    End If
End Sub

Se alguém puder me ajudar serei grato....

Obrigado!